Final answer:
The word 'for' is used to indicate a duration of time, whereas 'since' refers to the starting point of an ongoing action. For example, 'I have studied for two hours' versus 'I have been studying since 2 PM.' It's crucial to use these words correctly to express time periods accurately.
Step-by-step explanation:
Difference Between 'For' and 'Since'
When expressing the duration of an action, English speakers use 'for' and 'since' with different meanings. The word 'for' is used to describe a period of time. For example, 'I have studied for two hours.' In contrast, 'since' is used to refer to the starting point of an action or a condition that continues to the present. For instance, 'I have been studying since 2 PM.' It's important to choose the correct word to convey the time accurately.
Some phrases that might be used similarly to 'for' and 'since' include 'given that', 'because', and 'owing to', among others. However, these phrases are more causative, providing a reason rather than expressing duration or start time like 'for' and 'since'. For instance, 'I'm studying because I have a test tomorrow.'
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